Footwear system having a sole adaptable to different dimensions of shoes

ABSTRACT

A footwear system includes at least two uppers of different sizes having respective first sole members which are different in dimension, and a second sole member for attachment to either one of the first sole members. The second sole member is adjustable at least in dimension to be adaptable to dimensions of both of the first sole members and has at least one hollow part whose dimension is changeable for adjustment the second sole member. When the second sole member is attached to one of the first sole members, the hollow part is adjusted to a first width. When the second sole member is attached to the other first sole member, the hollow part is adjusted to a second width different from the first width.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to articles of footwear, more particularly to afootwear system including a sole which can be changed in dimension andshape so that it adapts to different dimensions and shapes of shoeuppers.

2. Description of the Related Art

Referring to FIG. 1, a shoe 1 typically has an outsole 12 attached to anupper 11. The outsole 12 includes a toe part 121, a shank part 122 and aheel part 123 as shown in FIG. 2 and has a tread member (not shown) atthe bottom thereof. In order to accommodate varying sizes of thewearers' feet, shoes are designed with different standardized sizes,such as from size numbers 5 to 12 with an interval of ½ between twoconsecutive numbers.

When a new series of shoes are to be manufactured, it is necessary toproduce different sizes of soles to be assembled with varying sizes ofshoes. As different sizes of soles require different individual moldsfor forming the soles, a large number of molds need to be prepared, thusresulting in considerable expenses for manufacturing shoes of differentsizes. In addition, the preparation of a large number of molds for allsizes of shoes would take a lot of time which may delay the launching ofshoe products into the market.

U.S. Pat. No. 6,418,641, discloses a shoe which includes an upper, ashock absorbing insole affixed to the upper, a frame secured to theinsole, and a sole made up of plural separate parts which are adhesivelysecured to the frame. The frame is provided with cutouts, whereas theseparate parts of the sole are spaced apart from each other. Thepurposes of the cutouts in the frame and the gaps between the parts ofthe sole are to dissipate or minimize the reaction forces exerted on thefoot upon impact. This patent suggests nothing relevant to theadjustment of the dimensions or the outline of a sole. U.S. Pat. No.5,729,912 discloses an adjustment system for the adjustment of thedimensions of a shoe in a plurality of discrete locations of a sole ofthe shoe. The adjustment system is incorporated into the sole atadjustment locations defined by grooves or voids of the sole. Theinvention in this patent is aimed at only adjusting the width and shapeof the sole of a shoe to adapt to the foot of an individual wearer,rather than different dimensions of shoes.

In order to facilitate the production of soles and to reduce the costsof preparing molds for fabricating soles, it is desirable that a seriesof shoes having different sizes can be manufactured by using a commonmold for producing soles.

SUMMARY OF THE INVENTION

An object of the present invention is to provide a sole which isadjustable in dimension and size to adapt to different dimensions andshapes of shoes.

Another object of the present invention is to provide a footwear systemin which a series of shoes having different size numbers can bemanufactured by using a common mold to produce soles.

Still another object of the present invention is to provide a sole whichcan be adjusted in both width and length to adapt to different sizes andshapes of shoes.

According to the present invention, a footwear system comprises: atleast two uppers of different sizes having respective first solemembers, each of the first sole members having a toe part, a heel part,an intermediate part, and a peripheral end surrounding the toe, heel andintermediate part, the first sole members being different at least indimension; and a second sole member for attachment to either one of thefirst sole members and being adjustable at least in dimension to beadaptable to the dimensions of both of the first sole members, thesecond sole member having at least one hollow part whose dimension ischangeable for adjustment of the second sole member. When the secondsole member is attached to one of the first sole members, the hollowpart is adjusted to a first width, and when the second sole member isattached to the other one of the first sole members, the hollow part isadjusted to a second width which is different from the first width.

The second sole member may be composed of a plurality of separate soleportions. The hollow part may be a cutout formed in the second solemember or a gap defined by the separate sole portions. The overall widthof the second sole members can be changed when the width of the hollowpart is adjusted in a transverse direction of the first sole member. Andthe overall length of the second sole member can be changed when thewidth of the hollow part is adjusted in a longitudinal direction of thefirst sole member.

As described above, the second sole member which is composed of aplurality of sole portions. Although a sole having plural separate partslike the second sole member used in the present invention is disclosedin U.S. Pat. No. 6,418,641, nothing disclosed in this patent suggeststhat such a sole can be used for adjustment of the dimension and shapeof the sole so as to adapt to different sizes of shoes. In addition,while U.S. Pat. No. 5,729,912 discloses an adjustment of the dimensionand shape of a sole, it fails to suggest that the dimensions of a solebe adjusted to adapt to different sizes and shapes of shoes. In view ofthe fact that U.S. Pat. No. 6,418,641 suggests nothing relating toadjustment of the dimension of a sole and that U.S. Pat. No. 5,729,912merely teaches that a sole should be adjusted in an individual shoe toadapt to the foot of an individual, the prior art never suggests that asole be adjusted to adapt to different dimensions and shapes of shoes.

BRIEF DESCRIPTION OF THE DRAWINGS

Other features and advantages of the present invention will becomeapparent in the following detailed description of the preferredembodiments of the invention, with reference to the accompanyingdrawings, in which:

FIG. 1 a perspective view of a conventional shoe;

FIG. 2 a plan view of a sole of the conventional shoe;

FIG. 3 is an exploded view of a first preferred embodiment of thepresent invention;

FIG. 4 is a perspective view of the first preferred embodiment;

FIG. 5 is a plan view of the first preferred embodiment;

FIG. 6 is an exploded view of an alternative example of the firstpreferred embodiment including additionally an alignment indicator;

FIG. 7 is a perspective view of another example of the first preferredembodiment incorporating a sewing line;

FIG. 8 is a perspective view of further example of the first preferredembodiment incorporating insert pieces;

FIG. 9 shows that a second sole member of the first preferred embodimentis attached to a first sole member having a small size;

FIG. 10 shows that the second sole member of the first preferredembodiment is attached to another first sole member having a large size;

FIG. 11 is an exploded view of a second preferred embodiment of thepresent invention;

FIG. 12 is a perspective view of the second preferred embodiment;

FIG. 13 is an exploded view of a third preferred embodiment of thepresent invention;

FIG. 14 is a perspective view of the third preferred embodiment;

FIG. 15 is an exploded view of a fourth preferred embodiment of thepresent invention; and

FIG. 16 is a perspective view of the fourth preferred embodiment.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Before the present invention is described in greater detail, it shouldbe noted that same reference numerals have been used to denote likeelements throughout the specification.

Referring to FIGS. 3 to 6, a first preferred embodiment of the footwearsystem according to the present invention includes a first sole member20 and a second sole member 30. The first sole member 20 is formed as adual-layered insole for attachment to an upper 2 and has an upper layer21 and a lower fabric layer 22 attached to the upper layer 22 (the upperand lower layer 21 and 22 are reversed in FIGS. 3 to 6 as the upper 2 isupside down). The upper layer 21 may be made from a material such as PE,nylon, PU, TPU, or glass fiber, or a composite material. The materialmay also be any other thermoplastic or thermosetting resin, eitherfoamed or unfoamed, or any other nonwoven fabric, or a combinationthereof. The insole or first sole member 20 has a flat top face 201 anda flat bottom face 202 which functions to assist in bonding the secondsole member 30 to the first sole member 20. The first sole member 20includes a toe part 23, an intermediate part 24, a heel part 25, and aperipheral end 26 surrounding the toe, intermediate and heel parts 23,24 and 25.

Of course, the first sole member 20 may also be used as a midsole or acombined midsole instead of an insole. The top and bottom of the midsole(not shown) may be in any shape desirable for practical use. Theadvantage of the midsole is that the midsole may be formed withprotrusions to fill the gaps formed upon adjustment of the distancesbetween the components of the second sole member 30 before the secondsole member 30 is attached to the first sole member 20. As such, themidsole can be assembled with the second sole member 30 precisely toform a perfect combination. If the midsole is made of a foamed material,in order to enhance the abrasion resistance against the ground surface,the midsole may be preformed with an indentation to fill high abrasionresistant outsole material.

The second sole member 30 is attached to the bottom face 202 of thefirst sole member 20 through adhesive bonding to serve as an outsole,and is composed of three sole portions, i.e. a front sole portion 31, arear sole portion 32 and a middle sole portion 33 all of which areprovided with tread surfaces, respectively. The front, rear and middlesole portions 31, 32 and 33 may be made of different materials accordingto varying physical and mechanical characteristics, such as flexibility,abrasion resistance, and comfortability, etc., required by the toe,intermediate and heel parts of a shoe. The front sole portion 31 iscemented to the toe part 23 of the first sole member 20 and has a frontperipheral edge 311. The second sole portion 32 is cemented to the heelpart 25 and has a rear peripheral edge 321. The front and rear soleportions 31, 32 are provided respectively with cutouts 312 and 322 whichgenerally extend along a longitudinal direction of the first sole member20 so that the widths of the front and rear sole portions 31, 32 may beadjusted by moving inward or outward the opposite lateral sides thereof.The cutouts 312, 322 may be provided in any suitable quantity and withany suitable dimension to meet the design of shoes to be manufactured.The middle sole portion 33 is cemented to the intermediate part 24 ofthe first sole member 20 between the front and rear sole portions 31 and32. The middle sole portion 33 has left and right peripheral edges 331which are curved and arranged to be flush with the peripheral end 26 ofthe first sole member 20, and left and right cutouts 332 adjacent to theleft and right peripheral edges 331. The cutouts 332 permit the left andright peripheral edges 331 to move inward or outward along a transversedirection of the first sole member 20 so that the middle sole portion 33is adjustable in width. The second sole member 30 can also be adjustedin length along the longitudinal direction of the first sole member 20.Adjustability of the dimension and shape of the second sole member 30will be detailed hereinafter.

As shown in FIGS. 4 and 5, the front, rear and middle sole portions 31,32 and 33 of the second sole member or outsole 30 are attached to thefirst sole member 20 and are spaced apart from one another with a gap“d1” between the front and middle sole portions 31 and 33 and with a gap“d2” between the middle and rear sole portions 33 and 32. The front andrear peripheral edges 311 and 321 of the front and rear sole portions 31and 32 are flush with the peripheral end 26 of the first sole member 20.

As shown in FIG. 6, to facilitate assembly, the bottom face 202 of thefirst sole member 20 may be provided with an alignment indicator, suchas aligning lines 203 which are formed through a printing process toindicate the positions at which the front, rear and middle sole portions31, 32 and 33 should be located. By following the aligning lines 203,the second sole member 30 can be easily and rapidly assembled with thefirst sole members 20. Apart from the aligning lines 203, the first solemember 20 may also be provided with any other indication means suitableto identify the locations of the front, rear and middle sole portions31, 32, 33, such as a mark which may be formed on the first sole members20 during the molding process thereof.

Assembly of the second sole member 30 with the first sole member 20should not be limited to use of an adhesive bonding process. Anyconventional means suitable for securing the first and second solemembers 20 and 30 may be used in the present invention. As shown in FIG.7, the second sole member 30 may be attached to the first sole member 20by means of a sewing line 301. Apart from this, interlocking elements,such as male and female engaging elements, may be provided between thefirst and second sole members 20 and 30 to interconnect the same. Foreffective connection, an adhesive may be provided between the contactsurfaces of the first and second sole members 20 and 30.

Referring to FIG. 8, the footwear system of the present invention mayadditionally include insert pieces 34 to fill the cutouts 312, 322 andthe gaps d1 and d2 of the second sole member 30. The insert pieces 34may be formed by cutting or molding to correspond to the shapes anddimensions of the gaps d1 and d2 and the cutouts 312, 322. The materialof the insert pieces 34 may be any foamed or unfoamed thermoplastic orthermosetting material, or rubber. Examples of them are PU, EVA, etc.The insert pieces 34 may be colored and formed with various shapes toprovide improved aesthetic effects.

The dimension and shape of the second sole member 30 can be adjusted andchanged to be adaptable to differently sized first sole members 20 whichare to be assembled with different sizes of uppers (not shown). As shownin FIG. 9, when the second sole member 30 is assembled with the firstsole member 20 having a small size with a length “L1”, the dimensions ofthe overall outer periphery of the second sole member 30 must be reducedby pressing inward the peripheral edges of the front, rear and middlesole portions 31, 32 and 33 to decrease the width of the cutouts 312,322 and 332, and the width of the gaps d1 and d2 of the second solemember 30 must be reduced to d1′ and d2′. Thereafter, the front, rearand middle sole portions 31, 32 and 33 are secured to the first solemember 20 by a cementing or sewing process.

As shown in FIG. 10, when the second sole member 30 is to be assembledwith the first sole member 20 which has a large size number with alength “L2”, the dimensions of the overall outer periphery of the secondsole member 30 must be increased by stretching outward the peripheraledges of the front, rear and middle sole portions 31, 32 and 33 toincrease the width of the cutouts 321, 322 and 332 and the width of thegaps d1 and d2 of the second sole member 30 must be increased to d1″ andd2″. Thereafter, the front, rear and middle sole portions 31, 32 and 33are secured to the first sole member 20 by a cementing or sewingprocess.

As mentioned above, the second sole member 20 may be adjusted to changeboth the width and the length thereof so that the second sole member 20is adaptable to be assembled with shoes having lengths L1 and L2.Therefore, said shoes may be manufactured by using a common mold forproducing the second sole members 30 thereof. As such, it is notnecessary to prepare plural molds to produce individually a plurality ofdifferently sized second sole members 30.

The advantages of the present invention will be explained further by wayof examples of manufacturing a series of shoes with size numbers rangingfrom 8 to 11 (American grades). In this series of shoes, the sizenumbers of the largest and smallest outsoles are respectively 11 and 8.The differential dimensions (not exact values, only approximate valuesare provided for reference) between the two outsoles are as follows:

-   -   (1) about 30 mm (the differential length measured along a        longitudinal direction)    -   (2) 10-15 mm (the differential width of a toe part measured        along a transverse direction)    -   (3) 15-20 mm (the differential width of a heel part measured        along a transverse direction); and    -   (4) about 10 mm (the differential width of an intermediate part        measured along a transverse direction)        There are altogether seven size numbers (8, 8.5, 9, 9.5, 10,        10.5 and 11) from size numbers 8 toll. Conventionally, outsoles        for different size numbers cannot be fabricated by using the        same mold. According to the present invention, the aforesaid        size numbers may be divided into two groups, for example, a        first group including size numbers 8, 8.5, 9 and 9.5, and a        second group including size numbers 9.5, 10, 10.5, and 11. As        such, the differential dimensions between the greatest and        smallest sizes of the outsoles in each group are reduced to        halves of the above described differential values, and are        listed as follows:    -   (1) about 15 mm (the differential length measured along a        longitudinal direction)    -   (2) 5-7 mm (the differential width of a toe part measured along        a transverse direction)    -   (3) 7.5-10 mm (the differential width of a heel part measured        along a transverse direction); and    -   (4) about 5 mm (the differential width of an intermediate part        measured along a transverse direction)

Since each of the front, rear, and middle sole portions 31, 32 and 33 ofthe second sole member 30 can be adjusted at two opposite sides thereof,the dimensional changes needed at each of the opposite sides thereof arewithin the differential dimensions which may be obtained by furtherhalving the aforesaid differential dimensions and which are stated asfollows:

-   -   (1) about 7.5 mm (the differential length measured along a        longitudinal direction)    -   (2) 2.5-3.5 mm (the differential width of a toe part measured        along a transverse direction)    -   (3) 3.75-5 mm (the differential width of a heel part measured        along a transverse direction)    -   (4) about 2.5 mm (the differential width of an intermediate part        measured along a transverse direction)

Based on the above proposed dimensions, the front, rear, and middle soleportions 31, 32 and 33 of the second sole member 30 may be designed withproper deformable and adjustable characteristics. Of course, theaforesaid 8 to 11 size number series may also be divided into threegroups, four groups and so on, in order to provide various designs forthe second sole member 30 of the present invention.

Referring to FIGS. 11 and 12, a second preferred embodiment of thefootwear system according to the present invention comprises a secondsole member 30I which includes a front sole portion 31I, a rear soleportion 32I, a middle sole portion 33I and left and right lateral soleportions 34I. The front sole portion 31I is attached to the toe part 23of the first sole member 20 and has a cutout 311I. The rear sole portion32I is attached to the heel part 25 and has a cutout 321I. The twolateral sole portions 34I are attached to left and right sides of theintermediate part 24 of the first sole member 20. The middle soleportion 33I is attached to the first sole member 20 between the frontand rear sole portions 31I, 32I and between the lateral sole portions34I. Gaps d3, d4, and d5 are formed between the front and lateral soleportions 31I, 34I, between the rear and lateral sole portion 32I, 34I,between the lateral and middle sole portions 34I, 33I. The middle soleportion 33I is so shaped that it projects partially into the cutouts311I and 321I of the front and rear sole portions 31I and 32I, and thegaps d3 and d4. The width of the cutouts 311I and 321I and the width ofthe gaps d3, d4 and d5 can be adjusted to change the dimensions andshape of the second sole member 30I.

In addition to the first sole member 20 and the second sole member oroutsole 30 or 30I, the footwear system of the present invention may alsoinclude a third sole member or midsole which has a one-piece structureor a multi-piece structure. Referring to FIGS. 13 and 14, a thirdpreferred embodiment of the footwear system according to the presentinvention comprises a first sole member 20, a second sole member oroutsole 30II attached to the bottom face 202 of the first sole member20, and a third sole member or midsole 40 connected to a top face 201 ofthe first sole member 20. The second sole member 30II is substantiallysimilar to the second sole member 30 of the first preferred embodimentexcept that the second sole member 30II additionally includes flanges331II projecting from left and right sides of a middle sole portion 33IIto the first sole member 20, and a generally U-shaped flange 321IIprojecting from the peripheral edge of the rear sole portion 32II to thefirst sole member 20. The third sole member or midsole 40 includes afront sole portion 41, a rear sole portion 42 and a middle sole portion43 and has substantially the same configuration as the second solemember 30II except that the third sole member 40 does not include theflanges 331II and 321II. The flanges 331II and 321II of the second solemember 30II extend from the second sole member 30III to the first andthird sole members 20 and 40 and cover partially the peripheral end ofthe first sole member 20 and the edges of the middle sole portion 43 andthe rear sole portion 42 of the third sole member 40. The dimensions ofthe third and second sole members 40 and 30II are adjustable like thesecond sole members 30 and 30I of the previous embodiments.

Referring to FIGS. 15 and 16, a fourth preferred embodiment of thepresent invention includes a first sole member or insole 20I, a secondsole member or outsole 30III and a third sole member or midsole 40I. Thefirst sole member 20I has front and rear protrusions 21I, whereas thethird sole member 40I has front and rear protrusions 41I. The secondsole member 30III includes left and right sole portions 31III each ofwhich extends from a toe part 23I to a heel part 25I of the insole 20Iand resembles the shape of a half of a sole. The left and right soleportions 31III are spaced apart in a transverse direction of the firstsole member 20I. Each of the left and right sole portions 31III has aflange 311III projecting from the second sole member 30III to the firstand third sole members 20I and 40I. In assembly, the flanges 311III ofthe left and right sole portions 31III extend around the peripheral endsof the first and third sole members 20I and 40I. A gap 33III is formedbetween the left and right sole portions 31III, and the front and rearprotrusions 21I and 41I of the first and third sole members 20I, 40Iextend between the flanges 311III in the gap 33III. By changing thewidth of the gap 33III, the second sole member 30III can be adjusted tobe adaptable to different uppers which are of the same length butdifferent in width. In view of this embodiment, the present inventionalso provides a second sole member which can be adjusted to be adaptableto the dimensions of shoes that have the same size number but differentwidths.

While the present invention has been described in connection with whatis considered the most practical and preferred embodiments, it isunderstood that this invention is not limited to the disclosedembodiments but is intended to cover various arrangements includedwithin the spirit and scope of the broadest interpretations andequivalent arrangements.

1. A footwear system comprising: at least two uppers of different sizeshaving respective first sole members, each of said first sole membershaving a toe part, a heel part, an intermediate part, and a peripheralend surrounding said toe, heel and intermediate parts, said first solemembers being different at least in dimension; and a second sole memberfor attachment to either one of said first sole members and beingadjustable at least in dimension to be adaptable to the dimensions ofboth of said first sole members, said second sole member having at leastone hollow part whose dimension is changeable for adjustment of saidsecond sole member, wherein, when said second sole member is attached toone of said first sole members, said hollow part is adjusted to a firstwidth, and when said second sole member is attached to the other one ofsaid first sole members, said hollow part is adjusted to a second widthwhich is different from said first width.
 2. The footwear system asclaimed in claim 1, wherein said second sole member includes at leasttwo sole portions which are formed as separate pieces and which arespaced apart to have therebetween a gap that defines said hollow part.3. The footwear system as claimed in claim 1, wherein said second solemember has a cutout to define said hollow part.
 4. The footwear systemas claimed in claim 2, wherein said sole portions are attachedrespectively to said toe part and said heel part.
 5. The footwear systemas claimed in claim 4, wherein each of said sole portions includes afront sole portion and a rear sole portion, said front and rear soleportions having respectively peripheral edges substantially flush withsaid peripheral end of one of said first sole members attached to saidsecond sole member.
 6. The footwear system as claimed in claim 5,wherein each of said front and rear sole portions has at least onecutout to define said hollow part.
 7. The footwear system as claimed inclaim 5, wherein said front and rear sole portions are made of differentmaterials.
 8. The footwear system as claimed in claim 5, wherein saidsecond sole member further comprises a middle sole portion attached tosaid intermediate part between said front and rear sole portions.
 9. Thefootwear system as claimed in claim 8, wherein said middle sole portionhas at least one cutout to define said hollow part.
 10. The footwearsystem as claimed in claim 8, wherein said middle sole portion has leftand right peripheral edges flush with said peripheral end of one of saidfirst sole members attached to said second sole member.
 11. The footwearsystem as claimed in claim 1, wherein said second sole member furtherincludes an insert piece to fill said hollow part.
 12. The footwearsystem as claimed in claim 6, wherein said second sole member furtherincludes an insert piece to fill said gap and said cutout.
 13. Thefootwear system as claimed in claim 5, wherein said second sole memberfurther includes left and right lateral sole portions which are providedbetween said front and rear sole portions and which are spaced apartfrom each other, and a middle sole portion disposed between said leftand right sole portions and between said front and rear sole portions.14. The footwear system as claimed in claim 1, wherein at least one ofsaid first sole members has a multilayered structure which includes atleast one fabric layer for attachment to said second sole member. 15.The footwear system as claimed in claim 2, wherein each of said firstsole members has a surface to be in contact with said second solemember, said surface being provided with at least one alignmentindicator to indicate at least one position at which at least one ofsaid sole portions is to be located.
 16. The footwear system as claimedin claim 2, wherein at least one of said sole portions has a flangewhich projects from said second sole member to one of said first solemembers attached to said second sole member and which covers a portionof said peripheral end of said one of said first sole members.
 17. Thefootwear system as claimed in claim 2, wherein said second sole memberis composed of left and right sole portions each of which extends fromsaid toe part to said heel part and which are spaced part in atransverse direction of said first sole members to define said gap. 18.The footwear system as claimed in claim 17, wherein each of said leftand right sole portions has a flange which projects from said secondsole member to one of said first sole members attached to said secondsole member, said flanges of said left and right sole portions extendingaround said peripheral end of said one of said first sole members, saidone of said first sole members having front and rear protrusions toproject between said flanges of said left and right sole portions fromsaid peripheral end.
 19. The footwear system as claimed in claim 1,further comprising a third sole member to be connected to one side ofone of said first sole members opposite to said second sole member. 20.The footwear system as claimed in claim 19, wherein said third solemember is adjustable in dimension and shape like said second solemember.